A biosensor is a sensor which applies a biological material to a molecule identification element by utilizing a molecule recognition ability of the biological material such as a micro-organism, an enzyme, or an antibody. To be specific, the biosensor utilizes a reaction which occurs when an immobilized biological material recognizes a target specific component, consumption of oxygen by respiration of a micro-organism, an enzyme reaction, luminescence or the like. Especially, practical use of a biosensor utilizing an enzyme reaction has been progressed, and it is utilized in the medical field and the food field.
Hereinafter, an example of a biosensor measurement system utilizing an enzyme reaction will be described with reference to FIG. 13.
A biosensor measurement system 20 includes a biosensor 30 having a sample application part 30a at its front end, and a measurement unit 21 which measures the concentration of a specific component in a liquid sample that is applied to the sample application part 30a. 
The measurement unit 21 includes a display part 22 which displays the measurement result, and a support part 23 in which the biosensor 30 is inserted.
The biosensor 30 is obtained by laminating a cover 31, a spacer 33, a reagent layer 35, and an insulating substrate 36 as shown in FIG. 14. The cover 31 has an vent hole 32 in its center. The spacer 33 has an approximately rectangular sample supply channel 34. The reagent layer 35 supports a reagent which enzymatically reacts with the specific component in the liquid sample. The insulating substrate 36 comprises polyethylene terephthalate or the like, and an electrode layer is formed at its surface. The electrode layer is divided by a laser or the like, thereby forming a working electrode 37, a detection electrode 38, and a counter electrode 39.
Next, a liquid sample measurement method by the biosensor measurement system 20 will be described. The description will be given of a case of measuring the glucose concentration in blood.
When the biosensor 30 is inserted in the support part 23 of the measurement unit 21, a constant voltage is applied between the working electrode 37 and the counter electrode 39.
When blood is applied to the sample application part 30a of the biosensor 30, the blood penetrates along the sample supply channel 34 by capillary phenomenon to reach the reagent layer 35, and then an enzyme reaction occurs between glucose in the blood and the reagent supported by the reagent layer 35. A change in current between the working electrode 37 and the counter electrode 39 which occurs upon the enzyme reaction is detected. Then, the glucose concentration in the blood is calculated based on the detected current change value, and the calculation result is displayed on the display part 22 of the measurement unit 21.
By the way, since the enzyme reaction has a large temperature dependence, the measurement precision is degraded due to a temperature change or the like during the measurement.
So, in order to improve the measurement precision, there has been proposed a biosensor measurement system in which a measurement apparatus is provided with a temperature correction algorithm for correcting the measurement result according to the ambient temperature during the measurement by using a temperature correction table which shows the relations between prepared glucose concentrations and temperature correction amounts (Patent Document 1).
Furthermore, as biosensor measurement systems for improving the measurement precision, there have been proposed a biosensor measurement system which measures the temperature of the biosensor itself with a thermal conductive layer provided on the insulating substrate 36 of the biosensor 30, and corrects the measurement result on the basis of the temperature of the biosensor itself (Patent Documents 2 and 3), and a biosensor measurement system having a temperature detector at the support part 23 of the measurement device 21, which measures the temperature of the biosensor 30 itself by bringing the biosensor 30 inserted in the support part 23 in contact with the temperature detector, and corrects the measurement result on the basis of the temperature of the biosensor itself (Patent Document 4).
Patent Document 1: Japanese Unexamined Patent Publication No. Hei. 8-503304
Patent Document 2: Japanese Published Patent Application No. 2001-235444
Patent Document 3: Japanese Published Patent Application No. 2003-42995
Patent Document 4: International Publication No. 2003/062812